An aerodrome, (or airdrome) or airfield is a term for any location from which aircraft flight operations take place, regardless of whether they involve cargo, passengers or neither. The terms are used in International Civil Aviation Organization (ICAO) documents, for example in the Annex to the ICAO Convention about aerodromes, their physical characteristics and their operation. The term “airport” is also used in the aviation industry. There is not a clear difference in meaning between the two terms in colloquial usage; however, the term airport may imply a certain stature (having satisfied certain certification criteria or regulatory requirements) that an aerodrome proper may not have achieved. That is to say, all airports are aerodromes, but not all aerodromes are airports. As used herein, the terms “airport”, “airfield”, or “aerodrome” shall be used interchangeably within the meaning of the invention.
Airports are divided into landside and airside areas. “Landside” land is airport land that is outside of the runway areas within the airport. Landside areas include parking lots, public transportation train stations, tank farms, grassy areas, mowed turf, access roads and areas along highways near airports. “Airside” land usually refers to land alongside of runways within the airport. Airside areas include all areas accessible to aircraft, including runways, taxiways, ramps and tank farms. Access from landside areas to airside areas is tightly controlled at most airports. Passengers on commercial flights access airside areas through terminals, where they can purchase tickets, clear security, check or claim luggage and board aircraft through gates. The waiting areas which provide passenger access to aircraft are typically called concourses, although this term is often used interchangeably with terminal.
A lawn is an area of aesthetic and recreational land planted with grasses or other low durable plants, which usually are maintained at a lower and consistent height. In recreational contexts, the specialized names turf, pitch, field or green may be used, depending on the use of the field and the continent. Many different species of grass are used, depending on the intended use and the climate. For example, coarse grasses are used where active sports are played, and finer grasses for ornamental lawns looked upon. Some grasses adapted to oceanic climates with cooler summers and others to tropical and continental climates with hotter summers. Often a mix grass or low plant types is used to form a stronger lawn when one type does better in the warmer seasons and the other in the cooler climates.
According to a study from the University of Illinois and report entitled Species, Endophytes and Wildlife—A Primer on Turf Management for Airports, by Bruce Branham, Theresa Kissane, and Edwin Herricks, (Departments of NRES and CEE, University of Illinois, it is estimated that since 1988, global wildlife strikes have been responsible for at least 163 aircraft strikes and resulted in the death of more than 194 people.
The FAA wildlife strike database has recorded over 121,000 (Civil and USAF) wildlife strikes between 1990 and 2010. During the five years between 2006 to 2010, there was an average of 26 strikes reported each day. As global travel increases every year, it is estimated that the number of strikes increases accordingly. Most alarming is that the FAA estimates that only 20% of wildlife strikes are reported.
Branham et al. report that birds were involved in 97.5% of the strikes. The reported strikes increased from 1,744 in 1990 to 7,236 in 2005. From 1990 to 2005, 695 strikes involved deer, and 79 involved reptiles. The white-tailed deer population has increased from 0.3 million in 1900 to 17 million in 2005. From 1980 to 2005, the resident Canada goose population has risen 7.9% each year. Over the same time period, the population of the red-tailed hawks increased 1.9%; the population of wild turkeys increased 12.7%; the population of turkey vultures increased 2.2%; and the population of double-crested cormorants increased 4.9%. FIG. 1 illustrates the incidents of wildlife strikes from 1990 to 2005, Table 1 demonstrates the recorded statistics of the states with the most reported wildlife strikes. FIG. 2 is a graphic representation illustrating the time of year when most wildlife strikes occur in the United States.
TABLE 1States with the Most Reported Bird Strikes, 1990-2005STATENUMBER OF STRIKESCalifornia5590Florida4447Texas4245New York3632Illinois3139Pennsylvania2335Ohio2119
Deterring birds from water on or near airports is an important part of many bird strike reduction programs. The FAA has made a significant effort of deterring birds from the ponds and waterways near airports. Overhead wires made with various materials and in a variety of patterns can reduce bird use of such areas, although the costs of such efforts can be substantial. As part of a study to determine whether increasing the spacing of grid wires reduces material and initial labor costs while still deterring birds, NRWRC researchers placed lines 50-feet apart over wastewater ponds in South Carolina and monitored bird usage. The total number of waterfowl using the ponds increased. Canada goose numbers declined, while mallard, ring-necked, and ruddy duck numbers increased.
The National Wildlife Research Center (NRWRC) conducts research to develop methods and provide guidance to the Federal Aviation Administration (FAA), airport operators, and the American public regarding the mitigation of bird-aircraft strike hazards. NRWRC has focused its research on understanding the nature of wildlife hazards at airports, developing management tools to reduce those hazards, and providing Wildlife Services' biologists, airport personnel, and FAA officials with information on the latest strategies for controlling wildlife hazards.
In a NRWRC study in Illinois, lines 15-feet apart over narrow streams in the State also showed no significant difference in total bird use before and after line installation. Mallards, great blue herons, and great egrets all used the protected areas. Waterfowl using the protected areas might have perceived the overhead lines as protection from avian predators. These findings show that an integrated approach is necessary to haze birds effectively at protected locations.
Understanding how birds perceive and react to deterrent methods is important for controlling property damage and protecting human health and safety, as well as preserving the aesthetic value of places shared by birds and people. In a recent study, NRWRC researchers investigated the reaction of captive brown-headed cowbirds (Molothrus ater) and rock pigeons (Columba livia) to a perching deterrent that caused slight pain and the reaction of Canada geese (Branta canadensis) to an area deterrent designed to provoke a fear response. Objectives of the study were to determine (1) the efficacy of these two techniques, (2) the latency of each technique, (3) if members of a flock would communicate the apparent risk among themselves and to naive flock members, and (4) if the birds would habituate to the techniques. The results of this study showed that both methods, when activated, were effective in displacing birds. With each method, each bird had to experience the technique, as video observations showed no evidence of communication among flock members or to naive birds that were introduced to the flock. However, when researchers deactivated each method after an initial period of activation, birds returned to the protected areas. No habituation to either technique was observed. NRWRC proposes that these results indicate that the loss of comfort due to direct pain or the perception of risk due to chronic random stimulus remains a critical component in stimulating bird avoidance behavior.
Another current means of “wildlife management” at airports refers to the practice of employing sharpshooters to kill any animal or bird that is located on airport property or vicinity.
In 2009, following the USAir 1549 bird strike and emergency landing in the Hudson River, the FAA started a number of initiatives to mitigate bird and wildlife strikes by airplanes. The FAA made its entire bird strike database available to the public. Over the last three years the FAA has received 21,489 strike reports—7,545 strikes in 2008; 9,484 in 2009; and 4,460 through July 2010.
The FAA issued a certification alert to airport operators on Jun. 11, 2009, reminding them of their obligation under the FAA regulations to conduct mandatory Wildlife Hazard Assessments and the FAA provides Airport Improvement Program funds for assessments and for the development of a follow-up Wildlife Hazard Management Plan, if needed.
The FAA also has a working relationship with the Smithsonian that goes back to the 1960s, when the two agencies, along with the military and aircraft manufacturers, began working together to identify the bird species from remains after a strike. Bird identification helps airfield personnel implement habitat management schemes that discourage birds from airfields and provides information so aircraft manufacturers can better design engines and aircraft to withstand the impact of bird collisions.
In 2001, the FAA began working with the United States Air Force to develop a radar system for detecting and tracking birds on or near airports. Because of the rapid development of avian radar, the FAA switched its research focus and began evaluating commercially available avian radar. Specifically, the FAA wanted to know how airport operators could use the technology to help implement their wildlife hazard mitigation programs.
For the last 15 years, the FAA and the United States Department of Agriculture (USDA) have conducted a research program to make airports safer by reducing the risks of aircraft-wildlife collisions. The research efforts designed to improve wildlife management techniques and practices on and near airports include methods for making airport habitats less attractive to species that are the most dangerous in terms of aircraft collisions. This is accomplished by studying which species use the airport property, how they behave in that environment, and why they are attracted; techniques for controlling species by restricting access to attractive features like storm water ponds; and technologies for harassing and deterring hazardous species.
The FAA cosponsors the Bird Strike Committee-USA as part of its continued public outreach and education effort to increase awareness within the aviation community about wildlife hazards. This is an international forum where biologists, engineers, airline personnel, and others come together to exchange ideas and learn about the latest technology to mitigate wildlife hazards.
The tremendous focus, effort, research, studies and current wildlife deterrent techniques clearly illustrates that there exists a great need for a safe, effective and sustainable method of deterrence to wildlife at airports. The current invention introduces a turf management strategy described herein that makes great progress into addressing this continuing need.
In most airport protocol, the field is composed of existing weedy turf grass vegetation requiring regular mowing. Existing turf grass installations are input intensive, requiring high levels of labor and materials such as mowing, equipment, chemicals and fertilizers (for example, petrocarbons), water, and energy, which are required in order to properly maintain the airport runways and surrounding areas. Hence, in addition to being wildlife attractants, existing airfields can be environmentally destructive—contributing to massive overloads of storm water runoff, pollution of our waterways and oceans, depletion of groundwater supplies, and additional green house gas emissions.
Existing airport turf grass installations typically include known wildlife attractants such as bluegrass, rye grass and broadleaf annual and perennial weeds, which are problematic in that they are attractants to grazing wildlife, such as geese, deer, and grasshoppers, all of which are especially troublesome for airports. Other problematic animals include (but are not limited to) rabbits, mice and other rodents, squirrels, groundhogs, as well as many other species of birds. Predators such as fox, coyote, and hawks are attracted to the lower trophic levels of animals, including insects, which are attracted to the typical weedy turf grass of airfields. These animals are all hazardous to aircraft. The Federal Aviation Administration attempts to discourage wildlife from entering airside land by encouraging airports to specify less favorable landside habitat conditions as one extra layer of protection. The resulting environmental and economic impact demonstrates a currently unmet need in modern turf grass landscapes at airports.
At the 29th Meeting for Bird Strike Committee, Bill Walmsley discusses best practices for establishing endophyte grasses at airports. (2010 Best Practice Guidelines for Novel Endophyte Grass Establishment at Airports). The report, like others, discusses only tall fescues, ryegrasses and cool season turf grasses. Currently, tall fescues are used at some airports in an attempt to deter wildlife from the airfields. Other grasses commonly used for airport turf include Kentucky bluegrass as a cool season species and Zoysiagrass and buffalograss as warm season turf grass species.
AgResearch Ltd., New Zealand's largest Crown Research Institute, an independent state owned research and development company, investigated the use of endophytes in ryegrass and fescues for wildlife management, stating that the bird strikes cause a challenge of $1.5 billion to the aviation industry annually. Specifically, AgResearch Ltd. focused its study on two turf species of grass—Jackal, a tall fescue variety, and Colosseum, a ryegrass, which are now on the market through PGG Wrightson Seeds. The tall fescue was chosen for airfields and is being trialed at major airports in New Zealand. In May 2011, AgResearch and scientist Chris Pennell received the DuPont Innovation Award that recognizes the commercialization and outstanding science and technology in Australasia.
Despite the recent success and spreading popularization of tall fescues, the use of tall fescues does not resolve the various challenges of airfield management as discussed herein. The tall fescues can grow to heights of 48 inches or more, and therefore require steady mowing resulting in a great economic burden on airports which carries into greater costs of air travel to the consumer.
As the aviation industry is faced with potential for extensive loss of life and property due to wildlife strikes each year, the frequency and consequences of wildlife activity dictate that these occurrences remain in the forefront of every airport's wildlife management plan. Beyond the environmental, social and financial consequences of wildlife strikes, a report presented by Larry A. Dale at the Aug. 2008 USA/Canada Meeting of the Bird Strike Committee, goes further to outline the legal liability faced by airports and their management. In addition to federal and state policies, the court system has also become involved to ensure that airport management take steps to conduct accurate assessments and to develop and implement an effective wildlife management plan for wildlife hazard mitigation.
According to the invention, it is disclosed herein that fine fescues grass species can be used successfully according to the invention to replace existing typical airside and landside turf, which are often very weedy wildlife attractants that require continuous mowing at airports. Current airfield turf grass maintenance necessitates continuous mowing to maintain the grass at acceptable heights. Not only does the mowing flush and mutilate insects and small animals and produce straw, both of which attract hazardous wildlife to runway safety areas, but mowing also is an energy and labor intensive practice that inherently increases the potential for operational conflicts and safety risks with other ground equipment and aircraft on the airfield.
To date, with many national and global efforts to address the stated problems, it has not been known to address the combined features of wildlife deterrence and the need for reduced mowing resulting in improved airfield management and the benefits of improved storm water control, decreased pollution, decreased gas emissions, temperature moderation, biodiversity conservation and other safety, environmental and economic benefits disclosed herein. The invention utilizes fine fescues successfully grown on airfields in a manner never before appreciated and provides an operative result that had not been achieved heretofore.